A charter bus was headed from St. Louis, Mo. to Queens, N.Y. on Sunday when it overturned around 7 a.m. Sunday.
The bus rolled onto its side as it was exiting from Interstate 70 eastbound to I-270 northbound on the city's west side.
Medics took 15 children and four adults who were on board to area hospitals. The group was on a robotics field trip, according to police. An officer said their injuries were minor.
A spokesperson for the Federal Motor Carrier Safety Administration told 10TV News that the Maryland bus company operating the bus had not responded to three recent letters which had requested a compliance audit.
The company, believed to have been operating the bus under the name Platinum Magic Carpet Ride LLC, had been issued a warning by the state of Maryland about potential license revocation within 10 days.
The FMSCA said the company was attempting to set up a mandatory inspection prior to the crash.
Crash investigators had not ruled Sunday on the cause of the accident.
The FMCSA was planning to send its own investigators to the bus company to look into the cause of crash and see if it could have been prevented.
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